Not clear to me exactly what they mean by ‘TV viewing’. Is this limiting YouTube numbers just to content like television shows and movies, or just when viewed on a streaming device like a stick or a smart TV?

Any way you slice it, feels very apples to oranges to me. My use cases for watching YouTube videos is such a different experience from sitting down and watching a show or a movie. At the end of the day, I guess it all competes for the same attention though /shrug